Better Living through Chemistry
I’ve been sick a few times this past month and it was hell. It was so bad I had to go on a course of antibiotics to help wipe out the infection. That got me thinking though, how do antibiotics even work? It’s just a pill, so how does the chemical know to go and kill only the bad bacteria, why not all our cells? Does it kill the “good” bacteria in our gut?
Well the bacteria are single celled little creatures that have something our human cells don’t, a rigid cell wall. This cell wall is made up of something called peptidoglycan. All antibiotics that end in –cillin work by interfering with the creation of that bacterial cell wall. They have a compound called beta-lactam that binds to these cell walls and inhibit its construction. So each particle of antibiotic is like a homing missile sent to take down the walls of the “bad cells”. Well kind of. They actually interfere with our “good” gut bacteria as well. A few studies show that it takes weeks for our gut flora to get back to normal working order. A small price to pay maybe.
Bacteria are very innovative though. I’m taking a molecular biology class and its really fascinating. One of the things we talk about a lot are “plasmids”. Plasmids are little pieces of circular DNA outside of the normal DNA jumble of a bacteria cell. It exists outside and can “evolve” or change very rapidly. It is through this that they can evolve proteins relatively quickly to be resistant to anything that comes along. So with this little trick, some evolved the ability to create a secondary protein to bind to the beta-lactam ring and make it useless. They essentially then became antibiotic resistant. Fortunately there are other antibiotics that work in many different ways. Unfortunately, bacteria now have plasmids so the race is and will forever be on.
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